Display Device

1. A device for controlling an operation of a display unit, the device comprising: a battery current control unit configured to adjust a magnitude of a low potential driving current to be applied to a pixel of the display unit, wherein the battery current control unit comprises: a comparator configured to compare a battery voltage converted from a battery output current with a threshold voltage, output a first logic voltage when the battery voltage is equal to or higher than a first threshold value, and output a second logic voltage when the battery voltage is lower than the first threshold value; an output controller configured to output a first control signal according to the first logic voltage from the comparator, and output a second control signal according to the second logic voltage; an output unit configured to output a first low potential driving voltage to the pixel according to the first control signal, and output a second low potential driving voltage to the pixel according to the second control signal, and the device further comprising a battery blocking unit configured to compare the battery voltage of a battery with a predetermined cutoff threshold value, and block the battery output current from flowing from the battery to the display unit when the battery voltage reaches the cutoff threshold value, wherein the predetermined cutoff threshold value used by the battery blocking unit is higher than a value of the threshold voltage used by the comparator of the battery current control unit.

2. The device of claim 1 , wherein the battery voltage corresponds to a value obtained by converting the battery output current to a voltage in proportional to a preset resistance value.

3. The device of claim 1 , wherein the output controller comprises: a logic unit configured to output a first selection signal according to the first logic voltage, and output a second selection signal according to the second logic voltage; a multiplexer configured to output a preset first register value according to the first selection signal, and output a preset second register value according to the second selection signal and; and a pulse width modulation controller configured to output the first control signal according to the first register value, and output the second control signal according to the second register value.

4. The device of claim 3 , wherein the output unit comprises a buck boost configured to increase a voltage of an output terminal of the output unit in proportional to a turn-on period of a switch, and decrease the voltage of the output terminal in proportional to a turn-off period of the switch, wherein the turn-on period and turn-off period of the switch are controlled based on one of the first and second control signals applied to the switch, and the second control signal has a longer turn-on period than the first control signal.

5. The device of claim 1 , wherein the output unit includes: a switch operating according to the first or second control signal of the pulse width modulation controller, an inductor selectively connected with the switch and connected between a voltage boosting node and a ground, and a capacitor connected between the voltage boosting node and the ground.

6. A display device, comprising: a display unit including data lines, gate lines crossing the data lines and pixels; a voltage generating unit configured to generate driving voltages for driving the display unit based on a voltage from a battery; and a data driver configured to convert input image data into data voltages and output the data voltages to the data lines, wherein the voltage generating unit includes: a battery current control unit configured to control a magnitude of a low potential driving voltage applied to cathode electrodes of the pixels according to an amount of a battery output current flowing from the battery to the voltage generating unit, wherein the battery current control unit is configured to increase the low potential driving voltage when the battery output current is equal to or greater than a predetermined threshold value, and a battery blocking unit configured to compare a battery voltage converted from the battery output current of the battery with a predetermined cutoff threshold value, and blocks the battery output current flowing from the battery to the voltage generating unit when the battery voltage reaches the cutoff threshold value, wherein a value of the threshold voltage used by the comparator is set to be lower than the cutoff threshold value used by the battery blocking unit.

7. The display device of claim 6 , wherein the battery current control unit comprises: a comparator configured to compare the battery voltage converted from the battery output current of the battery with a threshold voltage, output a first logic voltage when the battery voltage is equal to or higher than a first threshold value, and output a second logic voltage when the battery voltage is lower than the first threshold value.

8. The display device of claim 7 , wherein the battery current control unit further comprises: an output controller configured to output a first control signal based on the first logic voltage from the comparator, and output a second control signal based on the second logic voltage from the comparator; and an output unit configured to output a first low potential driving voltage based on the first control signal from the output controller, and output a second low potential driving voltage based on the second control signal from the output controller.

9. The display device of claim 8 , wherein the output controller comprises: a logic unit configured to output a first selection signal based on the first logic voltage, and output a second selection signal based on the second logic voltage.

10. The display device of claim 9 , wherein the output controller further comprises: a multiplexer configured to output a preset first register value based on the first selection signal output from the logic unit, and output a preset second register value based on the second selection signal output from the logic unit; and a pulse width modulation controller configured to output the first control signal based on the first register value output from the multiplexer, and output the second control signal based on the second register value output from the multiplexer.

11. The display device of claim 8 , wherein the output unit is configured to increase a voltage of an output terminal of the output unit in proportional to a turn-on period of a switch, and decrease the voltage of the output terminal in proportional to a turn-off period of the switch, and wherein the turn-on period and turn-off period of the switch are controlled based on one of the first and second control signals applied to the switch.

12. The display device of claim 11 , wherein the second control signal has a longer turn-on period than the first control signal.

13. The display device of claim 11 , wherein the output unit includes: the switch operating according to one of the first and second control signals, an inductor selectively connected with the switch and connected between a voltage boosting node and a ground, and a capacitor connected between the voltage boosting node and the ground.

14. The display device of claim 8 , further comprising: a gamma voltage generator configured to generate a gamma voltage at a first luminance value in response to the first low potential driving voltage, and generate a gamma voltage at a second luminance value lower than the first luminance value in response to the second low potential driving voltage.

15. The display device of claim 7 , wherein the battery voltage corresponds to a value obtained by converting the battery output current of the battery to a voltage in proportional to a preset resistance value.